Paper: ‘Glacierized Headwater Streams as Aquifer Recharge Corridors, Subarctic Alaska’.
Arctic river discharge has increased in recent decades although sources and mechanisms remain debated.
Here we link glacier runoff to aquifer recharge via a losing headwater stream in subarctic Interior Alaska.
Our findings suggest a linkage between glacier wastage, aquifer recharge along the headwater stream corridor, and lowland winter discharge.
Observations of increased river discharge in summer and winter span the scientific community and Arctic residents.
High-latitude mountain glaciers represent an overlooked source to subarctic river discharge and aquifer recharge.
Our results suggest a linkage between glacier melt, headwater discharge, aquifer recharge, and lowland winter streamflow that may be hydrologically important also in other semiarid glacierized regions within and outside the subarctic.
Our measurements show that an Interior Alaska headwater stream lost significant amounts of its annual water (46%) to the underlying aquifer, while glacier runoff represents a significant share (>15%) of annual discharge under both low (3%) and high (60%) glacier coverage.
The glacier mass loss has likely served as the dominant supply to the Tanana River’s long-term increase in annual and winter discharge considering no commensurate increase in Interior Alaska precipitation.
We conclude that the role of mountain glaciers on subarctic watershed hydrology and permafrost deserves increased attention, especially considering the well-documented decline in ice cover and increased winter river discharges.